Tape formulation application

The concept of pyriprox) en tape formulation and application technology is described in Figure 2. Essentially, the concept of the delivery system is to utilize the whitefly s attraction to the yellow tape formulation. Such attraction causes whitefly to land on the tape formulation and thereafter come into contact with pyriproxyfen which will result in the unhatching activity against whitefly eggs. Finally the tape formulation controls the next genereation of whitefly. 

Application research of tape formulation was done to determine the best arrangement, application timing and setting position. 

Figure 8, the tape formulation showed good whitefly control by both methods. However, from the viewpoint of working time needed for application, horizontal method appeared to be more practical. This test was conducted by preventive measure where the tape formulation was set at the beginning of the cultivation period. 

Application research indicated that the tape formulation should be applied horizontally along the ridges by preventive measure at the beginning of cultivation (4). Pyriproxyfen tape formulation keeps an excellent whitefly control through the cultivation period by this application method. Additionally, working time needed for application was significantly reduced by using tape formulation in comparison with the use of spray application. 

PVC Pressure-Sensitive Tapes. Formulated PVC plastisols are used in automotive applications. A pressure-sensitive adhesive-coated closed-cell PVC tape has replaced butyl glazing tape in some glazing applications. Other applications include automotive, trucks and trailers, mobile homes, steel building erection, metal door gasketing, and sound deadening. Both single-face and double-face tapes are available in various thicknesses, widths, and densities. The pressure-sensitive adhesive is believed to be of the acrylic type. 

Another important application area for PSAs in the electronic industry focuses on the manufacturing, transport and assembly of electronic components into larger devices, such as computer disk drives. Due to the sensitivity of these components, contamination with adhesive residue, its outgassing products, or residue transferred from any liners used, needs to be avoided. Cleanliness of the whole tape construction becomes very critical, because residuals like metal ions, surfactants, halogens, silicones, and the like can cause product failures of the electronic component or product. Due to their inherent tackiness, acrylic PSAs are very attractive for this type of application. Other PSAs can be used as well, but particular attention has to be given to the choice of tackifier or other additives needed in the PSA formulation. The choice of release liner also becomes very critical because of the concern about silicone transfer to the adhesive, which may eventually contaminate the electronic part. 

Thermoplastic block copolymers were used for pressure-sensitive and hot-melt rubber adhesives as from the middle sixties. These adhesives found application in packaging, disposable diapers, labels and tapes, among other industrial markets. The formulation of these adhesives generally includes an elastomer (generally containing styrene endblocks and either isoprene, butadiene or ethylene-butylene midblocks) and a tackifier (mainly a rosin derivative or hydrocarbon resin). 

Applications and Formulation. Pressure-sensitive adhesives are most widely used in the form of adhesive tapes. The general formula for a pressure-sensitive adhesive includes ail elastomeric polymer, a tackifying resin, any necessary fillers, various antioxidants and stabilizers, if needed, and cross-linking agents. 

Bulyk. Butyl-based materials are sold in the form of preformed tapes, thermoplastic hot melts, and one-part solvent-releasing sealants. Butyl polymers are made by the copolymerization of 97-98 mol % isobutylene with 2-3% isoprene. Another butyl-based polymer, polyisobutylene, is produced by the polymerization of isobutylene. Formulations of butyl-based sealants also include plasticizer, filler, and lackifier resins. Poly butenes are common plasticizers for butyl sealants. Solvents, such as mineral spirits, are used for the one-part solvent-releasing formulations. As the solvent leaves the typical one-part butyl, the sealant hardens and loses its elastomeric ability. This limits the use of solvents to low movement applications where durability is not of high concern. 

The widespread applicability of di-O-methylisosorbide as a medium for chemical reactions or as a solvent for pharmaceutical formulations is well documented. In some cases, an additive synergism of the solvent and the solute was observed. Some typical examples mentioned include that it acts as a solvent for muscle-relaxant drugs, which are otherwise difficultly soluble,226 and is used for topical and other types of pharmaceutical formulations,227,228 transdermal controlled-release films229 and tapes,230 anthelmintic solutions,231 antimycotic emulsions,232 and for the treatment of skin disorders, such as eczema.233... 

MEK is also used in solvent-based adhesives, in printing ink formulations, as a solvent in magnetic tape manufacture, and is the most common solvent used in dewaxing lubricating oils. Of all these applications only an increasing consumption of magnetic tapes is likely to grow in methyl ethyl ketone use. 

Cables via the powder-in-tube (PIT) method The approach is especially suited to processing Bi-2223 into leads and cables for power applications. A silver or silver alloy tube, filled with the partially reacted precursor powders formulated to yield Bi-2223, is drawn down to a wire 1-2mm diameter. The wire is rolled into a tape if that is the required form, usually with a width-to-thickness ratio of approximately 10 1. The composite is then heated to 800-900 °C when the powder partially melts. The recrystallization process is controlled and the pure Bi-2223 phase develops with large grains oriented so that the Cu-O planes lie parallel to the silver surface to optimize Jc. 

Although tapes, films, or coatings applied from solvent solution make up the majority of the solid epoxy adhesives, formulations in the form of a powder or shaped solids can also be employed in certain applications. These are manufactured using the second or third technique described above. 

The final thickness of epoxy tape or film adhesives is on the order of 5 to 15 mils. These adhesives may be soft and tacky, or stiff and dry, depending on their formulation. The soft and tacky products are valuable in products requiring application to contoured or vertical surfaces. If the product is especially tacky, a release liner (e.g., polyethylene film, coated paper) is generally used to keep the film from blocking. The stiff and dry products are generally used for flat surfaces where speed and ease of application are required. 

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